How to Handle Your Best Friend Dating Your Brother
by Veterization
Summary: Part of the "How to Date Your Best Friend's Brother" AU series that focuses on Scott's POV through Stiles and Derek's relationship. Or, in which Scott goes from being annoyed by his grumpy older brother to actually sort of appreciating the guy.


_Disclaimer: _I do not own Teen Wolf.

_Notes: _I haven't updated this verse in ages but I want to thank everybody who's still been asking for more and enjoying the first two parts! I still have a few more ideas on what to add to this series and I hope it won't take nearly as many months as this one did. I still really love the whole Scott/Derek as brothers dynamic and am excited to continue it.

* * *

Scott's pretty sure that the only time that he and his brother ever get along is when they're forced to bathe together as little tots and, under a wordless agreement to not flick shampoo in each other's eyes, cohabit the bathtub with little to no fussing or screeching. It is something of a miracle even back then and never lasts more than thirty minutes of lukewarm peace among the suds.

They're still young, Scott two years old and proudly counting the days to his fourth birthday and Derek six years old and never letting Scott forget it. He's too good for playing in the mud, too good for squishing worms in his hands, and too good for sippy cups. He knows all of his multiplication tables and Scott is happy if he can touch all of his toes. Only when their mother is kneeling by the bathtub putting dollops of foam on their heads and cooing at them is when they can coexist without Derek secluding himself in his room where it's mature, intelligent, and absolutely boring.

Now and again Scott will splash too hard in the water and Derek will glare at him with the anger of much older, scarier businessmen until Scott starts wailing and their mother restores peace by making more bubbles. Even Derek, who isn't amused by foam beards, likes playing with bubbles.

Maybe it works because when he's doused like a wet dog with his hair dripping in his face and his prepubescent limbs angled awkwardly into the tub, Derek isn't nearly as much of a big boy as he is when he's dry and puffed up to full capacity. He's just a young boy with arms too long for his body and back sprinkled with the beginning of acne and these are all things Scott can easily laugh at, and because he's two years old and cute, he gets away with it. Then their mother wraps them up in a huge fluffy towel that smells like soap and Scott shakes his head free of the excess water like a dog caught with the garden hose while their mother vigorously rubs them dry.

Years later, now fully aware of his multiplication tables, Scott definitely isn't up for taking baths with Derek anymore.

* * *

Worse than anything else, even his annoying habits of putting the milk in the bowl before the cereal or never letting Scott so much as breathe on his share of the toys, Derek is a huge killjoy.

His bed's just softer. Scott can't explain it, because his mother swears that it's the same mattress. Derek's seems larger. Derek's seems bouncier. Derek's doesn't squeak as much.

Scott remembers the day in kindergarten when he and Jackson Whittemore were still friends. Their friendship, the definition of youthful ignorance, lasted a grand three days with its highpoint being when Scott first discovered that Jackson had a trampoline in his backyard. He remembers jumping high enough to touch the clouds and feeling them tickle his cheeks, the feeling of flopping onto his stomach and bouncing back up like a popcorn kernel dancing around a skillet, and the way it made his legs feel when the hops that would normally propel him two feet into the air skyrocketed him at least five. And then Scott popped Jackson's basketball on pure accident and their friendship rapidly disintegrated.

Scott loves that feeling of hopping to the sky—he's pretty sure that's how astronauts feel during every launch—and he's wanted to recreate it ever since he was introduced to Jackson's yard. His feet don't bring him the same momentum, but he happens to find something nearly as awesome: Derek's bed.

"We'll probably crash through the ceiling and land on the sun," Scott says to Stiles solemnly when he tells him about the way Derek's mattress turns regular leaps into catapults. Stiles' eyes widen to the size of tree trunks at the prospect, so they pad over the hall to Derek's room and creak open the door to find it vacant.

"Woah," Stiles says. Scott totally gets it. He's always blown away at the size of Derek's room, which might have something to do with his own body being comparatively tinier. He's only six years old and Scott is easily impressed. "Are you sure your brother doesn't mind us being in here?"

Scott tunes out the question. _Of course_ Derek would mind, because Derek's a wet blanket who would probably read the dictionary for fun rather than act like an actual twelve-year-old. Scott has no idea what being a twelve-year-old entails, but if it requires the maturity of an old curmudgeon who shouts at the kids who so much as tiptoe on his lawn Scott wants to stay blissfully six forever. He counts on Derek being busy elsewhere to leave him and Stiles in peace to jump on his bed, because his bed is full of fluffed pillows and is at least twice the size of Scott's bed and isn't nearly as cluttered with the stuffed llamas Scott really, really wanted for his last birthday. It's calling out to him.

They clamber onto the bed, and right away, it gives them the view of grown-ups. Scott feels like a real adult from this height, a bed and a mattress and a thick sheet underneath him making him tall and a mighty presence in the room. All the trinkets on Derek's dresser that he never lets Scott so much as stand next to look miniscule from his height, and Scott desperately hopes that one day when he's an adult he'll be at least two feet taller than Derek so he can always feel this authoritative. Next to him, Stiles starts jumping in awe, because the mattress _is_ puffier and perfect for hopping. Scott jumps in tandem with Stiles, picking up momentum and brushing the ceiling with his hands.

"I think I know how birds feel now," Stiles says in breathless wonder, jumping harder. His tiny feet are clumsy and threatening to eventually pitch him off the bed, but Scott will deal with that when the tears come. Scott bends his knees and jumps even higher and swears his hair grazes the ceiling for a moment.

And of course, that's when the devil looms in the door to cast a wide shadow on their soaring and spoil the party like the tattletale in class who always tells the teacher when Scott is painting the desk with his markers.

"_What_," Derek says from the door, face contorting into something ugly and monstrous at the sight of his bed being debased and contaminated by childish rugrats. Scott stops hopping immediately and Stiles nearly topples over himself. "What is going on in here."

There's no tangible question mark at the end, which terrifies Scott a bit even if Derek is only twelve. Twelve isn't exactly a frightening age, full of sixth grade woe and the drama of learning division, but Derek gets a little weird about his things and his room and his life. Next to him, Stiles is at a total loss for words, a look on him Scott has never seen before.

"Nothing," Scott says, sharing one shifty glance with Stiles before their thought patterns sync and they both do what any respectable six-year-olds would do, and run from the room like fugitives caught at the crime scene.

* * *

Scott's favorite game is definitely hide and seek.

He doesn't know what's not to like. There's running, there's hiding, and there's the ultimate moment of climax when he's ducked into the dryer trying not to spoil the game with the laughter threatening to erupt from his throat when Stiles is prowling by, and the only thing that sucks about hide and seek is that Stiles is the only one who will ever play with him.

It's no offense to Stiles—Stiles is great to play games with. He doesn't cheat and he's not a sore loser who has to pine in a corner for hours after being discovered in the pantry. He picks hiding spots that challenge Scott but also don't take him all day to track down, like that clever spot behind the curtain in Scott's room or under the porch where the dirt is moist and dank and gets under his fingernails and always results in his mother vigorously cleaning them with paper towels in the kitchen. But sometimes playing with just Stiles gets incredibly boring. Stiles knows that Scott always has the urge to hide in the cellar behind the water heater during the first round and then goes straight for the spot barely big enough to fit a toddler under the couch during the second round, which makes for a rather predictable game. His mother is too busy to play, however, and Derek is definitely not an option.

Definitely not.

"Derek won't want to play," Scott says moodily from where he's laying in the grass trying his best to stare at the sun without blinking. It's a spring day and Scott can finally wear shorts again after a brutally endless winter, the grass damp and cool against the underside of his knees as he rolls on the ground. Stiles is next to him getting his freckles sunburned while he tries to make angel imprints in the grass, a few moments away from taking a nap in the warm sun. Scott pokes him in the side until his eyes spring open again.

"What if Derek is secretly a hide and seek master," Stiles says conspiratorially. "And he _loves_ games and fun but you never gave him a chance. He could know of places to hide that we've never even _thought_ of."

Scott snorts. Sometimes he thinks that Stiles expects miracles out of Derek just because he's older and has graduated from elementary school. Scott knows the ugly truth behind his brother, that Derek is nothing but one birthday away from spontaneously bursting into an old man so his exterior will finally match the cranky elderly soul he's harboring inside, and Stiles just hasn't realized it yet. As far as Scott can tell, there's nothing magical behind growing older, nothing earth-shattering behind being in high school, especially not the way Derek acts as the representative for teenager life. Scott has read from the Internet that teenagers are supposed to rebel and climb out the window at ghastly hours of the night to sneak into parties held in random basements, all things Derek couldn't seem to care less about.

But Stiles is already clambering to his feet and brushing the bugs off his ankles to head back inside and grab Derek, Scott helpless to stop him as he follows.

"You're not really going to ask him, will you?" Scott moans. Even if Derek, by some heavenly and unearthly miracle, agrees to play a game, Scott can't imagine him being much fun. He'd probably be a real stickler for the rules and constantly try to accuse Scott of cheating, even if Scott is the poster boy for staying morally honorable during hide and seek.

"Come on!" Stiles says, barreling through all of Scott's whines for him to ask the strange neighbor kids with the flamingos in the yard instead, ambling up the stairs to knock on Derek's door. It's closed, much like the gate to those creepy old mansions that end up being used as Halloween attractions.

"Who's there?" Derek's voice comes from inside his room. A part of Scott is extremely curious as to what sort of inventions Derek must be cooking up from the privacy of his room that he won't let anybody else see, and another part of him never, ever wants to know, especially when his mother always gently tells him to leave Derek be because he's going through a "delicate stage of manhood."

"Derek!" Stiles calls out boldly. "Come play hide and seek with us!"

The door opens a smidgen. A sliver of Derek's body is exposed as the door becomes ajar, his nose sticking out as he surveys the two of them critically. Scott has yet to outgrow him, which is incredibly frustrating. Derek's sixteen and has hit a growth spurt that makes him unfairly tall, but Scott stays appeased by the fact that his haircut is still awfully awkward and his hands are much too large for his arms. Stiles grins up at him, the same grin that would reduce most beefy, tattooed men to high-pitched cooing, and waits for an answer.

"Hide and seek?" Derek parrots slowly. He's staring at them like he's the Queen of England and they're just tiny impertinences he'd like to stomp out with the cavalry. Stiles nods.

"Come on, you can't want to stay in there forever," Stiles tries to peek inside the enigma of his room, but Derek's body blocks the way. "It's really nice outside."

For a second, Derek looks like he's considering it, and then he shuts his door with a rude finality after firmly saying, "No."

"Told you," Scott says right afterward, and Stiles, defeated, glares at him. He knocks on the door a few more times for good measure, a shrill, rapid knock that sounds like he's trying to replicate the rhythm of _We Are Family_ when Derek's thunderous footsteps approach the door again and Stiles and Scott both hightail it down the hall and back outside.

They flop down on the grass, rolling into the shade when the sun beats down on Stiles' reddening cheeks, and decide to climb trees instead. This time, Stiles learns his lesson and doesn't make the mistake of asking Derek to come join, instead racing Scott up to the top of the biggest oak in the yard and scrambling to perch himself on limbs shaking under his weight. They laugh from the treetop, branches of budding leaves in the way, and entertain the idea of making treehouses and mud pies.

"Promise me we'll never grow up like Derek," Scott says from where he's found the perfect nook in the trunk to rest his gangly body, feet kicking into the air.

And Stiles says, "I promise we'll never grow up at all, buddy."

* * *

Scott is squatting in the middle of the cold, rather isolated woods—not his most elegant state—failing in his attempt to look for viable firewood when the thought that maybe he's not cut out for camping first flits through his mind.

He will admit that he's having a good time for the most part. He's camping with his best friend and his dad and they have a whole tent to cause ruckus together in tonight, but he has to confess that when his mother first proposed the idea of going on a camping trip with the Stilinskis he hadn't entirely considered how rustic the experience was going to be. And now, here he is, a thirteen-year-old kid too young to die in the middle of the woods because a hungry badger found him meandering on his lonesome through the trees, wondering when on earth he even got separated from the others.

Mr. Stilinski—who, considering he's the one with the firearm—should have been the one to look for the wood when dusk was approaching and settling rapidly over the treetops, but instead it's the children doing the labor. The trek had begun with him, Stiles, and Derek all trudging through the leaves together in a combined effort to find fuel for the fire, but as usual, Derek is not a team player and wandered off on his own. Scott would've had no problem leaving Derek in the woods to fend for himself and go befriend some feral wolves if his best friend hadn't vanished as well, leaving him in the descending darkness with nothing but his cell phone to illuminate the ground. He has a handful of twigs that could be used for kindling in one hand that he's very much considering abandoning at this point as a cricket chirps loudly behind him as if ushering him along and urging him back to the campsite. He was sort of looking forward to those beans after a long day of hiking.

"There he is," a voice growls, and Scott whips around with his phone prepared to alarm whoever's attempting to sneak up on him with the lethally bright light of his home screen that he knows for a fact will burn retinas.

"Jesus Christ!" another voice says, definitely alarmed, and at least Scott knows that his self-preservation techniques aren't too shabby. It would've been even more impressive, however, if he had managed to thwart an actual threat rather than just Stiles and Derek.

Stiles promptly trips over his own feet and yelps when the phone gets shined in his face, falling back onto Derek who uprights him like he's nothing but a toothpick that fell in his way. He looks severely unamused, like having a flight risk as a little brother during a camping trip in potentially dangerous woods is the most irksome thing that life could have stuck him with, and proceeds to wrestle Scott's phone from his hands as the bright light lands directly on his face.

"Where have you been," Derek grumbles as Stiles smoothes the wrinkles from his jacket and lets his heartbeat return to normal. Scott is baffled that Derek is putting the blame on him when he was the one thoughtlessly abandoned in the undergrowth, undergrowth that could possibly be the habitat of bears and bobcats. He voices as much.

"There could be _bears_ around here," Scott hisses, equally miffed by the neglect of his best friend and his brother to check over their shoulders now and again just to make certain that Scott hadn't fallen prey to a bear trap. "How is this my fault when you're the ones who deserted me to fend for myself?"

"There aren't _bears_," Derek dismisses right away with a roll of his eyes that doesn't go unnoticed and instantly makes Scott feel like he's actually seven years old. Scott bodily throws his collection of twigs onto Derek's chest, watching them tumble to the floor after bouncing meekly off his torso, and Derek does little but set his jaw and roll his eyes again. Stiles steps in between them and pats Scott consolingly on the chest to keep the peace.

"Come on, Scott, it was Derek who was smart enough to trace your footsteps to find you again, so maybe throwing wildlife at him isn't the nicest thing to do," Stiles offers as mollification, petting his shoulder and leading him back around where Scott hopes the campsite is. He's lost his appetite for beans, especially when he sees that Derek has an entire armful of gargantuan chunks of firewood in his arm when all he managed to find was a handful of snapped twigs, and all he wants to do is pitch himself onto the air mattress that he'll have to blow up and fall asleep with the hopes that mosquitoes won't have nested in his pillowcase overnight.

They find the campsite embarrassingly quickly, in under two minutes, like if Scott had just turned around and walked he would've stumbled upon home base eventually, and he absolutely does not cross his arms and pout while they trudge to where Mr. Stilinski has set up a cooking station and has opened three cans of beans and corn for dinner.

"There's the man of the hour!" He hollers jovially when Derek sets down the wood and helps him prepare the fire. "Did you find all this wood yourself?"

"Stiles helped," Derek concedes before shooting Scott a glower. "Scott didn't."

"They left me in the woods to get _lost_," Scott murmurs petulantly. No one at the campsite offers any sympathy with the exception of a cricket that twitters from a nearby bush, and even that sounds more like laughter than a harmless chirp.

"What can I say, we make a good team," Stiles says with a grin as he grabs his hoodie from his duffel and wraps himself up in it as the nightly chill settles in, stopping to offer a fist bump to Derek.

Derek steadfastly ignores it.

* * *

Derek grows up pretty fast—not fast enough to catch up to his old, withered soul, but fast nonetheless—and suddenly the prospect of no longer having to share a bathroom and not being asked every ten minutes to turn down his music because _some_ respectable students are trying to _study_ for their precious _futures_ is very much a reality and no longer a far-off fantasy that Scott could only ever daydream of.

He puts more enthusiasm in helping Derek move out than he ever did in any other endeavors Derek ever engaged in, and even the small squabble over who was the rightful owner of the _Batman Begins_ DVD doesn't dampen Scott's spirits the day that Derek vacates his room and heads for the dormitory. His mother makes a huge fuss, crying in the car and making Derek promise that he'll visit the moment he gets settled and has free time. Scott is personally hoping that Derek's professors are going to be so gnarly and difficult to keep up with that Derek will be perpetually suffocating under his homework and won't ever be able to drive home. The idea of Derek no longer hogging the bathroom for private time like he's in the process of putting on extensive drag queen make up every morning and his sour face permanently leaving the house Scott has to live in is enough to make him want to sing karaoke out the windows.

Derek's dorm room is small, much smaller than his room at home, but Scott wastes no time pointing out all the ways that this residence is much better than home if only to guarantee that Derek never feels the desire to leave. Derek keeps sending him sharp glares every time Scott begins raving about the size of the closet and how clean the shower is like he's one hundred percent aware of how eager Scott is to get him out of his space. Scott can't help it if he's being insensitive; he's fourteen and is starting to understand the significance of privacy and the value of bathroom time.

He's heard stories of siblings who get along—a concept Scott has no familiarity with—who are miserable to see their brothers and sisters move out to start new lives and the rebellious experimentation phase of college, but Scott can only count positives out of this entire ordeal. No more Derek tattletaling to his mother every time Scott tries to hide a D grade under his bed, no more trying to boss him around as to how to make the perfect frozen waffle, no more being compared to Derek's unblemished grades and pristine records with the teachers, and no more struggling to get the upper hand with the remote. Finally, Scott gets to enjoy the luxuries of being a single child who gets spoiled rotten and gets an entire bathroom to himself whenever he so pleases to take an hour long shower.

When the last box is unpacked and all the decorations are up to turn the room from dull to slightly less dull, his mother weeps some more and wraps Derek up in a hug that lasts at least four minutes before letting go and stuffing his hands full of homemade cookies in case the first few hours of dorm life get rough. Then it's Scott's turn, who awkwardly shuffles forward and pats Derek on the back like he's embracing his demanding boss out of pure courtesy, and then they pull back and give each other curt nods that already make the goodbyes feel much too drawn out.

"See you around, bro," Scott says as casually as possible, patting Derek's arm and trying his hardest not to do a victory dance on the way down to the car.

* * *

The euphoric peace actually lasts for quite a few years, and up until Scott turns sixteen, Derek spends all of his time at the university without a single visit home that requires him bringing a suitcase of things and commandeering custody over the bathroom counter. He stops by in town sometimes to catch lunch with their mother or to come grab a few things left behind in his room, unperturbed since his move, and drive back to campus. It's a long drive, the sort of cumbersome travel that most people don't want to embark on frequently, and it lets Scott live a halcyon life that is essentially brotherless until Derek returns like the long lost prodigal son.

Scott broods about it at school for a good week even as Stiles tells him to keep his chin up and mother tells him to be welcoming, which is difficult considering that she spends three hours preparing Derek's favorite meal for his return when Scott hasn't had his favorite meal made in over a decade. He spends a lot of time scheming ways to get Derek out as quickly as possible, some simply threatening the guy to evacuate what is now firmly Scott's territory and some as intricately nefarious as leaving allergic substances littered about the crevices of his room.

They share the exact same uncomfortable hug they shared in parting years ago when Derek arrives with a humongous duffel bag that's a blatant indication that he plans on staying for longer than just an afternoon. He's never spent fall break at home before and Scott has to bite his tongue to keep from reminding Derek that it'd be incredibly unfortunate to break tradition when he could be working away as a busy bee in the solitude of his own dorm room rather than spending his time off with his family.

Thankfully, Derek spends most of his time alone, either reading in the living room for class or working out in the yard. He's a completely different person from the obstinate, weedy teenager that Scott remembers, one who's grown muscles and a face that actually resembles an adult's, not to mention perhaps better social skills. The last one, Scott doubts, but he has high expectations that maybe college has completely revamped his brother and whipped him into somebody approachable and amusing and actually interesting.

After that, memories of Derek's visit blur a bit, overridden with worthier recollections of Allison. He meets her a few weeks into his sophomore school year and remembers little else but her dimples and her sugary scent for a few days, so preoccupied with his youthful affections that he definitely lags in his best friend duties. He spends the nights he would normally spend playing Xbox with Stiles going on dates with Allison, ultimately resulting in Stiles being forced to hang out with Derek. The night he comes home after his and Allison's first date, giddy and lovestruck like he's back in second grade and has lost complete control of his inhibitions and his emotions, he sees Stiles and Derek camped out on the floor watching movies. Scott has watched movies with Derek, that is, before he completely surrendered the idea after Derek showed little to no interest in the plotlines or the special effects whatsoever, and the idea of Stiles awkwardly attempting to coax Derek into showing real human intrigue in a film is enough to make Scott feel like the worst best friend in the world for abandoning his best friend for a girl.

He mentally promises to make up all the hours Stiles spent trying to pass the time with Derek and desperately attempting to prove that he possesses a human heart after that evening, but Scott doesn't have the opportunity for a while with Allison in his life. Yes, he feels bad, and yes, Stiles deserves an entire weekend of marathonning X-Men as an apology, but if Stiles ever hooked up with Lydia and flew off the radar for a few weeks to revel in the joy that is _girls_, Scott would understand.

When he comes home one day and finds Stiles and Derek duking it out via video games, a pastime Derek has never once engaged in with Scott under the unspoken pretense that he was unspeakably too good for frivolities such as first person shooter games, he starts wondering if maybe it's Derek who's harassing Stiles into spending time with him, mostly because even the thought of anybody willingly hanging out with Derek is too much for his brain to handle. And he's trying to stomach logarithms, which his brain actually can handle, so that's saying something.

"Dude," Scott says after Stiles leaves to pick up some dinner for his dad, pulling Derek aside away from the disaster area that is the veritable pillow fort the two of them have set up to play Xbox on. "You gotta leave Stiles alone."

Derek stares like Scott's sprouted multiple heads. "I have to leave Stiles alone?" He parrots slowly, like the very demand baffles him. His eyebrows knit angrily together but Scott continues for the sake of Stiles, who will be endlessly appreciative that he won't have Scott's creepy older brother hovering over him anymore. Scott thinks this definitely makes up for all those nights he's ditched Stiles for dates.

"Look, maybe living in a college dorm with nobody else has made you a little lonely," Scott puffs up to appear more domineering and takes a breath. "But he's _my_ friend, okay?"

"Your friend," Derek's words are even slower now. He's staring down at Scott like he'd like very much to squeeze his face between a thigh master.

"Yeah, and he doesn't want to hang out with you, so just—just let him be when he comes over," Scott says. Derek looks stuck between incredulity and incredible aggravation at Scott's boldness, but he musters up the part of himself that vaguely knows how to be an acceptable sibling and claps a hand on Scott's shoulder.

"Got it," Derek says. He gets a little too close for comfort to Scott's face as if he wants to see what he'll do about it before he slips away, but Scott stands his ground against his intimidatory glare and congratulates himself on being a terrific friend.

* * *

A few weeks later, Stiles starts developing mysterious hickeys around his neck and shoulders that he tries in vain to hide. Scott doesn't actually notice until Stiles undresses in the locker room before lacrosse practice, not managing to slip his jersey on in time before Scott catches sight of a truly mean mark purpling his neck and trailing down his chest. He drops his lacrosse stick and pokes Stiles right on the chest where a mottled hickey has been clearly bitten onto his skin courtesy of what had to have been a wild and adventurous mouth, jaw dropping at the sight as Stiles' entire face turns tomato red. It makes Scott wonder exactly how long they've been there and exactly how out of the loop he's been ever since Allison's been taking up a generous portion of his headspace, like maybe Stiles has been trying to tell him for weeks about a girl he's met who's a fireball in bed except Scott hasn't been listening.

"Where'd that come from?" Scott demands, poking at it again. Stiles bats away his prodding hands and hotly slips his jersey over his head before others can come join the interrogation. Every part of his face from the tips of his ears to the hairline of his forehead is blushing the bright shade of humiliation, and no matter how embarrassed Stiles might be, Scott is not giving up until he gets answers.

"Nothing. You know, nobody," Stiles leans nonchalantly against the locker like they're discussing the weather and starts fiddling with his helmet. Scott's been friends with Stiles for a decade, and he knows perfectly well that whenever his hands start itching for something to fidget with there's secrecy at play. As long as he wasn't fooling around with Allison in the back of his Jeep after school, Scott's fine with his friend getting some action. Maybe they can even double date.

"Come on, dude, you gotta tell me," Scott says, lowering his voice when Stiles starts frantically shushing him as Greenberg walks by their conversation. "Was it Lydia?"

"Yeah, that's likely."

Scott leans in further. "It wasn't Allison, right?"

Stiles takes a moment to look personally offended before answering, and okay, Scott will admit that the question was blurted out of panic more than anything else. "I wouldn't do that to you!" He takes a deep breath and grabs Scott's shoulders. "It's nobody, all right? Just a casual one time thing. You know. Casual."

"So you're really not going to tell me who it is?"

"Uh, not now, that's for sure," Stiles says, sliding into his lacrosse shorts just as Finstock blows his whistle and starts beckoning players onto the field. He's definitely saved by the whistle, and Scott, not willing to do suicide runs just because he was too busy gossiping with Stiles in the locker room about whatever one night stand he managed to have in complete secret, lets it go and heads out to the field.

A few weeks later when he comes home with the purest of intentions to actually attempt his English homework but with the worst possible timing and sees Derek and Stiles in their birthday suits on the couch about to play ride the baloney pony, he feels incredibly, incredibly stupid.

* * *

It takes Scott a long time to realize that Scott and Derek being together actually has nothing to do with him.

He's not sure why he ever thought it did—maybe because he felt like Stiles was no longer his exclusively but was now custody of both him and Derek to be divided and shared on weekends, or maybe because it still baffles him that anybody would want to spend time with Derek without being forced to at gunpoint. He should have seen the signs ages ago back when Derek started making grilled cheese sandwiches for Stiles and they were laughing over the stovetop together like lifelong buddies, but Scott still spends at least one hour entertaining the possibility of Derek dating Stiles just to get back at Scott for doing a piss poor job of being a brother.

He has to admit, he wasn't exactly prepared for all the questions and introspection that him finding out about his brother and his best friend getting together would prompt. Aside from desperately trying to wash the image of Stiles' bare ass out of his head, he's starting to question his own shitty sibling skills and maybe even how Derek might be a real man, not just a mannequin who takes up room, with opinions and the ability to laugh and joke and entertain. If Stiles can see it, maybe Scott's been purposefully looking away and sticking fingers in his ears every time Derek attempted to share the better sides of his personality.

Now with Stiles as common ground between the two of them, Scott figures that now is a good as time as any to try and bond with Derek. He's waited sixteen years, but maybe if he keeps an open mind and prepares himself for the awkwardness of the first few weeks of attempting to form a friendship nearly two decades into a relationship after they've already lived together and shared baths, they could do it. He's pretty sure it would make Stiles happy.

He decides to start on his quest of brightening up his best friend's life on New Year's Eve when the opportunity presents itself for Scott to officially get involved in the secrets and the shenanigans.

Up until now, Scott's been processing their relationship and trying to deal with the sneaked kisses and the private smiles Derek only gives to Stiles when nobody's watching, but he's ready to become an active participant in the rule breaking. He gets why Scott and Derek haven't told anybody. There's the age difference that, although it's only six years, is six years too much for the law enforcement, and that's not mentioning the freakishly protective parents. And as much as Scott fears his own mother, he's willing to take one for the team and become a part of the secret-keeping and the sneaking around even if his own ass will be on the line when the day will inevitably come where the entire family knows exactly what their respective sons have been doing after school and during college breaks.

Derek thinks he's being discreet, but he's really not. Scott plus his mother plus a few odd colleague friends from the hospital are piled into the living room watching Dick Clark count down the minutes to the incoming new year getting increasingly trashed on martinis and straight vodka, and Derek's tucked into the kitchen on the phone with Stiles trying to explain why he can't sneak away from the party for the midnight celebration with the covert air of a rookie detective hiding behind a newspaper to spy on a suspect. Scott decides to put the poor guy out of his misery and slips away under the ruse of providing snacks for his mother's friends when he sees him whispering into his cell phone in the pantry, poking him on the shoulder to get his attention.

"Stiles wants to see you, right?" Scott asks, and Derek nods carefully after a moment's pause like he's considering the possibility of Scott using this information as blackmail against their mother, who would very likely skin Derek and season him for an impromptu roast if she knew that he was about to sneak out the window to make out with a minor to ring in the New Year. "I can cover for you."

"What?" Derek says, lowering the phone for a moment.

"I'll cover for you. I'll distract mom and say you went to the bathroom or something if she asks," Scott says. He's not always the fastest thinker under pressure, but he can come up with a convincing lie should he need to cook one up for the sake of clandestine Romeo and Juliet love. He blames his family and his best friend for making his life so complicated.

"Really?" Derek says, sounding rather surprised at Scott's helpfulness and cooperation. Scott nods and gives him a push in the direction of the back door.

"Just don't take forever. No sex, okay?" Scott feels the need to clarify that last bit. He can handle the idea of the two of them making out in the snow behind Sheriff Stilinski's shed, but the knowledge that they're actively swapping juices at the very moment that the ball drops and Times Square explodes into a drunken roar is too much information.

In the living room, somebody hollers for popcorn and Scott remembers why he was able to slip away to the kitchen in the first place. He rummages around in the pantry and gives Derek another push to the shoulder when he notices he still hasn't moved.

"What are you waiting for?"

Derek shakes his head free of the tiny smile sitting on his mouth and slides the back door open just enough to slip out without a sound. "Thanks," he says, and with that he's jumping the neighbor's fence and heading to the Stilinski household.

* * *

The electricity committing suicide and the storm knocking out all the power was not exactly what Scott had in mind for his evening, but he supposes that playing monopoly via candlelight isn't such a bad compromise.

When the lights first blitz off with a few ominous flickers, Scott is in his room texting Allison about math homework right before his phone slips through his fingers and falls into the dark abyss his room rapidly becomes. It's dark, a vortex of black shadows that he tries to feel his way through, and after a spectacular run-in with the wall and the desk, he fumbles his way downstairs like a blind person left unattended in the rain and waits for lightning to illuminate the staircases to eliminate any possibility of him showing up to school in crutches. Right when he reaches the landing, a flashlight shines in his face like a spotlight aimed directly at his eyeballs and Scott knocks it out of the way with a manly yelp of surprise. The flashlight tumbles onto the floor, and through another flash of lightning, Scott spies Derek's displeased face through the shadows.

"Thanks for that," Derek says dryly, feeling along the floor to locate the flashlight and hold it at an angle that no longer hits Scott directly in the face. He's home for spring break and had plans to go see Stiles before the storm started blowing rogue soccer balls and squirrels across the streets, forcing most of Beacon Hills to stay inside in the seclusion of their own dark holes. Scott could think of many things he'd rather do than be stuck with his brother in total darkness for a few hours, but he's made a pact to attempt to bond with the guy when such circumstances present themselves, so he slides by Derek to open the storage closet and feel through the piles of unused kitchen appliances and winter coats to locate the candles when three boxes of dusty board games proceed to fall on his head.

Half an hour later, that's how they find themselves sprawled on the living room with three stumpy candles and Monopoly stretched out in front of them. Derek rolls his dice and somehow manages to skip directly over _go to jail_. Lucky bastard.

"So what were you gonna with Stiles tonight?" Scott asks while he jiggles the dice in his hand. Derek gives him a look that Scott doesn't need an abundance of light to decipher. "Before the sex."

"Get some take out, probably, and drive around a bit," Derek says with a shrug.

"Wow, you're a terrible romantic," Scott says, snorting into his fistful of dice before he rolls. Damn. Right to jail. Derek furrows his eyebrows at him.

"Not all of us can jump right out of _High School Musical_ like you and Allison," Derek says through a mouthful of sarcasm.

"I sincerely hope that you're not making that reference because you've actually seen that movie," Scott says, and then their brief glaring match is interrupted by a loud crash from the kitchen.

He looks at Derek for instructions and watches as Derek freezes and gets to his feet, Scott fumbling for the baseball bat that he knows is under the couch and following him after tossing Derek the flashlight. They work in total tandem for those few seconds, tiptoeing to the kitchen and both avoiding the creaking floorboard before rounding the corner with their various props poised high in the air. Scott holds onto his bat as menacingly as he can as he comes face-to-face with—

"Oh my god, Scott, put down the bat!" Stiles' voice squeals from where he's standing, thoroughly soaked, in the kitchen. He looks like a doused dog who played in the rain for too long when he shakes off the endless drip of the raindrops on his clothes onto the wooden floor. Derek's shoulders unclench and he lowers his flashlight while Scott throws the bat over to the couch.

"Why are you sneaking through the back door?" He demands, and that's when Stiles holds up a dripping wet wicker basket that glows auburn in the lamplight.

"Surprise," Stiles says, throwing a drenched arm up in the air and spraying water over Scott with his sleeve in the process. He's making a puddle all over the floor but still looks oddly proud of himself for wrestling through the storm without accidentally being washed away by the heavy rain into the nearest gutter. "Romantic indoor candlelit picnic."

Derek slowly deflates and Scott tries not to burst out laughing.

"Sorry, Derek," Scott says, biting into his lip to keep the elegant snorts at bay. "But I'm getting some serious _High School Musical_ vibes here."

* * *

It honestly surprises Scott that it takes his mother a whole two years to find out her son has been deflowering an underage hyperactive boy who comes over every day. He would've figured a few months at best.

He has to admit—a part of Scott is surprised that Stiles and Derek even lasted two years. He has no idea how on earth their relationship works, but he knows it's absolutely nothing like the dynamic he has going with Allison. Allison and him are simple. He knows exactly what flowers to bring her to make her face light up and she knows that attempting to help him study for tests ends up being counterproductive. They eat lunch at the same table and share tidbits of their day and then go out to see movies and share milkshakes on the weekends. It's exactly what Scott expects out of a high school relationship, and then there's Stiles, who can't take his boyfriend to prom, who drives two hours out to campus to have sleepovers in a dorm room, and who has to duck out of sight every time a police cruiser drives by if he's out with Derek. Scott can't imagine keeping that up for two whole years, but they do. Scott supposes that's what Disney's always talking about when they mention "true love" and how it manages to usurp everything else, like nosy parents and laws against pedophilia.

Graduation was supposed to be an epic day, but he spends the better part of his evening trying not to sob uncontrollably into his hands while he's sandwiched in between Derek and Stiles and being interrogated by his mother and the sheriff. He doesn't know why he's clearly on the criminal side when he's very much innocent in all of these affairs. He may have covered for the two of them once, or twice, or thirty-six times, but he definitely didn't matchmake them and advocate the blatant law breaking. He spent most of his time pretending that his friend's relationship with his brother was purely platonic and that aside from some harmless hand holding, they were absolutely not having dirty gay sex. It worked, for about two years, before _now_ hits him like a demolition ball right in the ribs and all of his innocuous "keeping secrets" suddenly sound a lot like "abetting criminals."

It's the longest night of his life and he can't even imagine how much tighter the rusty chains are digging into Derek and Stiles' organs while they talk it out with the parents than they are to Scott. It honestly shocks him when they all walk away without any shiners and Derek still gets to keep his car. Scott was looking forward to watching their mother take Derek's Camaro away for at least a few days where justice rang through the world, because having sex with a minor for two years should have _some_ kind of punishment, preferably one that results in Derek brooding like a heartbroken teenager in his room for a bit while Scott dances in his own car and revels in his freedom, even if it is a piece of shit that looks like the beaten up adopted younger brother of Derek's car.

A part of him expects the sheriff to demand an end to this relationship and for his mother to approve whole-heartedly of the separation, but he's glad it didn't turn out concluding that drastically. It does shine some light on the possibility of the two of them breaking up, since couples do, after all, break up rather frequently, sometimes amiably and sometimes with slashed tires, and the idea is something that makes Scott's stomach churn with dread. Considering how horrified he was two years ago when he walked in on the two of them and how hard he denied that what he witnessed was true reality and not merely a cruel hallucination, he's a little surprised at his own personal growth and how supportive he's become of their relationship. Maybe it's because he can already imagine Derek turning into the same grumpy, anti-social turnip that he was ten years ago in the aftermath of the split, and it inspires Scott to have a talk with his brother that's two years overdue.

"So I really thought that mom would've broken you guys up," Scott says that night over the bathroom sink around his toothbrush. They're both foaming at the mouth with bubbly toothpaste, bent over the sink and cramped for room while their elbows bump. They're not tiny eight-year-olds anymore, turning sharing a bathroom into a daily spatial challenge lately.

"We would've found ways around it," Derek dismisses. Scott finds his devotion to Stiles oddly endearing as he spits into the sink and Derek follows a moment later.

"Well, my point is," Scott garbles around a mouthful of rinsing water. "I don't think you guys should break up."

"Wasn't really considering it," Derek says as he fits his toothbrush back into its holder and rummages around the cupboard for the mouthwash. "So I wouldn't worry about that."

"Good, because, well," Scott tries to mold his face into an expression that resembles something akin to intimidation. It works a little, because Derek pauses swishing the mouthwash around his tongue when he glances at Scott and takes in the seriousness of his countenance. "I'd kick your ass if you hurt Stiles."

Derek sputters around his mouthwash, spraying the mirror and biting his lip to hold back the laughter as he wipes the mirror clean once more and tries to keep the chuckles at bay. Scott punches him in the shoulder as hard as he can and Derek sobers up a bit by the time he turns to face Scott, putting an earnest hand on his shoulder and patting it.

"That's cute," he says around a shit-eating smile that Scott is not amused by. He shoves off Derek's hand and narrows his eyes in the fruitless hope of inspiring some fear in Derek. They're the same height, which Scott's always wanted, but Derek's crazy muscle mass is enough to make him feel inferior without height coming into the equation.

"I'm serious," Scott rumbles.

"I see that," Derek admits. "And so am I. And so is Stiles."

"Just—tell me you won't hurt him."

Derek smiles at that, a tiny discreet smile like he's thinking about Stiles, and it mollifies Scott to see Derek's sentimental side flit into view for a few seconds. He leans in and puts his hand back on Scott's shoulder, squeezing. "Remember a few years ago when you came up to me and told me to stay away from Stiles because he didn't like me?" Derek asks, and Scott sees where this is going. "This conversation is as unnecessary as that one."

He caps the mouthwash and sticks it under the sink, giving Scott one more amused smirk over his shoulder before he's out of the bathroom and into his room. It isn't exactly what he wanted to hear, as most of his conversations with Derek go, but it reassures Scott nonetheless.

* * *

The worst thing about having to deal with his best friend and his brother playing hide the salami is that sometimes he finds himself in situations where he overhears the aforementioned hanky-panky and is left with no choice but to get up at three in the morning and make a run to Walmart to buy earplugs to shop with all of the hipsters and the weirdos who feel the need to stock up on groceries in the middle of the night.

Tonight, Scott won't succumb to that urge. He's still hoping that maybe Stiles will have the decency to remember how thin the walls are and tell Derek that all sex should remain firmly sequestered in the dorm room where nobody but inebriated freshmen can hear them, but of course, Stiles says no such thing and Scott is left muffling his ears with his pillow trying to drown out the sounds of Stiles giggling like a schoolgirl while Derek undresses them with his teeth.

That's what Scott assumes they're doing, anyway. He wouldn't accept a million dollars to tiptoe over to Derek's room and check with his own eyes, but his imagination has been held hostage and tortured into producing various scenarios that may be occurring a wall away that is just as painful as what his eyes would have experienced firsthand.

"Jesus, Derek, _stop tickling_—" Stiles shrieks from the other room while Scott tries going to his mental happy place, like a babbling brook in the mountainside while Allison prances around the water with a crown of flowers in her hair. "_O-oh_, that's good."

Stiles groans, deep and pleasurable, through the wall. Scott groans as well, except his is full of distress and agony.

"Mmm, you look so pretty waiting for me to suck you off," Derek purrs, actually _purrs_ like a hungry cat prowling for a meal or an innocent teenage boy to feast on, and that's all Scott's going to be able to handle for his voyeuristic aural porn quota of the day. He bangs his fist on the wall as loudly as possible and listens as the room goes deadly silent. He guesses that Stiles is mortified right now while Derek's just upset that his little brother successfully thwarted a blowjob he was about to share with his boyfriend.

"Sorry, Scott!" Stiles calls through the wall, sounding properly scandalized.

Three hours later, they try their luck at sex again, and Scott is luckily deep in the arms of slumber, and when morning comes he stumbles out of bed to avoid eavesdropping on any adventures with morning wood, perched on the kitchen counter to enjoy a bowl of cereal. Twenty minutes later, Stiles makes an appearance, hair a little wild like either Derek's hands were relishing in tangling in it or a woodland creature made its nest there overnight. Scott supposes it's the former, but prays silently for the latter if only to avoid hearing any details.

"Morning," Stiles murmurs into the fridge as he gropes for the milk and grabs an extra bowl before sitting down across from Scott. He's wearing Derek's pajama pants and looks sleep mussed like he rolled out of bed two minutes ago to have breakfast with Scott.

"Rough night?" Scott asks, and then immediately regrets it when a smug quirk of a smirk tugs on Stiles' lips. That's absolutely all he wants to know. "Don't answer that."

"Duly noted," Stiles says, hiding his grin in his bowl. He reaches over to snag the box of cereal from Scott and pour in enough to overflow, little bits of Cocoa Puffs skittering over the table.

"Why aren't you still up there with Derek?"

"I don't know, hanging with my buddy Scott is much better than Derek's morning breath," Stiles says with a smirk that sends both of them into peals of laughter, and when they put their bowls in the sink and settle onto the living room floor to watch cartoons, Scott feels like he never could have been more wrong all those years ago when he was worried that Derek would steal Stiles away from him.

After all, he totally had Stiles first.

* * *

There's a rule in the household that Scott has created himself and followed more strictly than he ever has any other regulations ever put upon him, and that is to avoid Derek like the second plague whenever he gets sick.

Derek's ass already doesn't shine rays of sunlight out of it on normal, healthy days, but he's particularly grumpy on days when he's afflicted with a bad case of the sniffles and a scratchy throat. Most people just man up and sequester themselves with a box of tissues and some animated movies for a few days, but Derek likes to see his bacteria and his horrendously bad mood spread like an infectious disease to everybody around him. Scott always used to hide in his room under his mattress and let his mother take care of it when they were younger, but nowadays even his mother doesn't want to deal with Derek's drama, so Stiles surprised everybody by being completely immune to Derek's broodiness and being his caretaker when times got pretty germy.

Scott's thankful that Stiles is taking one for the team, but he still really doesn't know why he had to bring Derek to _their_ dorm room.

Stiles and Scott's dorm room is already the size of an abandoned outhouse left on the side of the road, complete with poor insulation and questionable plumbing, and Derek camping out on Stiles' tiny bed cocooned in all of the blankets that the whole floor has to offer isn't exactly making the place seem roomier. Now and again Derek will blow his nose into a tissue and it makes the sound of an elephant pitifully snorting into the wilderness before a painful birthing process begins, always prompting Scott to hightail it for the bathroom and camp out in there, where it's quiet and safe and sanitary. These are the things Scott absolutely hates Stiles for.

Stiles leaves for an hour to go get cold medicine, something Scott is pretty sure was actually just an excuse to leave Derek's vicinity for as long as possible, and Scott's stuck sitting on his bed sneaking glances at Derek wondering if he should be offering him tea or giving him the remote. It's Sunday morning and he has no homework and there's sitcoms on television, so giving away the remote would definitely count as a sin, especially when Derek would put on a documentary about endangered species of wolves or something else that teaches knowledge completely unnecessary in life. He waits patiently for Stiles to come home, wondering if Derek can fall asleep when he's practically drowning in his own snot and mucus, and when the sound of Stiles' key turning in the lock finally sounds, Scott is glad that little trial in his life is officially over.

He shoots off the bed and claps Stiles on the shoulder before disappearing down the hall of the dorm to grab something out of the vending machine, trying to make sleeping arrangements with Allison so he doesn't have to fall asleep to the sound of Derek's snot-induced snoring inside a quarantined dome of bacteria. When Allison tells him that she's having a sleepover with Lydia, Scott weighs the pros and cons of slumbering out in the hall with a sleeping bag. It could work.

Scott creeps his way back to his room to grab some essentials for a night of camping in the hallway and lets the door slide open a few inches so he can peek in and see how clear the coast is. If life loves him at all, Derek will be deep in the arms of slumber napping off whatever flesh-eating virus he's been infected with and Stiles will have his back turned firmly to the door.

They're not, naturally, and Scott peers through the ajar door waiting for the opportune moment to grab his sleeping bag and book it to the door before Stiles starts asking him to bring soup and get involved in the nursing duties. From his discreet vantage point, Scott sees that Stiles is kneeling by the bed smoothing Derek's hair away from his sweaty forehead and brushing his thumb over the accumulating stubble on his chin, a few private touches that seem to relax Derek out of his fever stupor. He sees Derek's hand lift through the sheets and curl around the nape of Stiles' neck while Stiles settles into the bed next to him and pillows Derek's head against his chest. It's intensely private and sickeningly sweet all at once, and Scott feels a bit like an intruder even just watching as Derek slings his arm over Stiles' ribs and buries his nose in the crook of Stiles' neck. Buried in piles of sheets and pillows, Derek looks oddly vulnerable and Stiles helplessly in love as he pets at the short strands of hair by Derek's ear, and it erases all doubts Scott ever had about the two of them.

He remembers years ago when he expected them to be a phase that would ultimately result in mega family tension, and he resented Derek for that, and maybe Stiles a little bit too, like they were responsible for potentially jeopardizing their family's awesome friendship for a quick romp in the sack. They seemed so unbelievably different back then, Stiles much too funny for Derek's sense of humor to handle and Derek much too guarded for Stiles' open nature to handle. And now it's been years of proving Scott wrong, years that finally convince Scott of the fact that his best friend is head over heels for his brother and his best friend couldn't have chosen anybody better to love him. It's refreshing to stare at their relationship as something solid and unshakable, as something that can make it through adolescence and meddling parents and even heaps of snot. Scott is amazed.

And then he remembers that he's trying to get out of providing chicken soup and promptly vacates the premises.

Stiles and Derek work pretty well together without him anyway.


End file.
